package com.hzz.framework.util;

import freemarker.template.Configuration;
import freemarker.template.Template;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.time.LocalDateTime;
import java.util.Map;

@Component
public class WordUtils {
    private static Configuration configuration = null;
    
    @Autowired
    private FreeMarkerConfigurer configurer;
    
    // classLoader.getResource()只能获取相对路径的资源
    // private static final String templateFolder =
    // WordUtils.class.getClassLoader().getResource("export").getPath();
    // class.getResource()可以获取绝对路径和相对路径
    // private static final String templateFolder = WordUtils.class.getResource("/export").getPath();
    
    // static {
    // configuration = new Configuration();
    // configuration.setDefaultEncoding("utf-8");
    // try {
    // configuration.setDirectoryForTemplateLoading(new File(templateFolder));
    // } catch (Exception e) {
    // e.printStackTrace();
    // }
    // }
    
    // private WordUtils() {
    // throw new AssertionError();
    // }
    
    public void exportMillCertificateWord(HttpServletRequest request, HttpServletResponse response, Map map, String title, String ftlFile) throws IOException {
        // configurer.getConfiguration().getTemplate("")
        Template freemarkerTemplate = configurer.getConfiguration().getTemplate(ftlFile, "UTF-8");
        // Template freemarkerTemplate = configuration.getTemplate(ftlFile);
        File file = null;
        InputStream fin = null;
        ServletOutputStream out = null;
        try {
            // 调用工具类的createDoc方法生成Word文档
            file = createDoc(map, freemarkerTemplate);
            fin = new FileInputStream(file);
            
            response.setCharacterEncoding("utf-8");
            response.setContentType("application/msword");
            // 设置浏览器以下载的方式处理该文件名
            String fileName = title + LocalDateTime.now() + ".doc";
            response.setHeader("Content-Disposition", "attachment;filename=".concat(String.valueOf(URLEncoder.encode(fileName, "UTF-8"))));
            
            out = response.getOutputStream();
            byte[] buffer = new byte[512]; // 缓冲区
            int bytesToRead = -1;
            // 通过循环将读入的Word文件的内容输出到浏览器中
            while ((bytesToRead = fin.read(buffer)) != -1) {
                out.write(buffer, 0, bytesToRead);
            }
        }
        finally {
            if (fin != null) {
                fin.close();
            }
            if (out != null) {
                out.close();
            }
            if (file != null) {
                file.delete(); // 删除临时文件
            }
        }
    }
    
    private static File createDoc(Map<?, ?> dataMap, Template template) {
        String name = LocalDateTime.now().hashCode() + "temp.doc";
        File f = new File(name);
        Template t = template;
        try {
            // 这个地方不能使用FileWriter因为需要指定编码类型否则生成的Word文档会因为有无法识别的编码而无法打开
            Writer w = new OutputStreamWriter(new FileOutputStream(f), "utf-8");
            t.process(dataMap, w);
            w.close();
        } catch (Exception ex) {
            ex.printStackTrace();
            throw new RuntimeException(ex);
        }
        return f;
    }
}
